<?phpclass ExhibitorsofExhibitionViewModel extends ViewModel{	 public $viewFields = array(        'exhibition_exhibit'=>array('exhibition_id','exhibit_id',		'user_id','count(distinct exhibition_exhibit.user_id)'=>'count'),				'exhibitor'=>array('id'=>'exhibitor_id','name_cn','logo_url',		'type_name','user_id'=>'uid','is_verified',		'_on'=>'exhibition_exhibit.user_id=exhibitor.user_id'),    );}?>